As one of eight National Primate Research Centers supported by the National Institutes of Health, the Southwest National Primate Research Center (SNPRC) facilitates research conducted by its own core scientists and also provides specialized nonhuman primate resources and technologies to a wide range of qualified external investigators. The SNPRC manages nonhuman primate breeding colonies, including rhesus macaques (Macaca mulatta), to provide adequate supplies of suitable macaques for biomedical research. To ensure adequate supplies of Specific Pathogen Free (SPF) rhesus macaques, a colony of approximately 260 individuals will be moved from the New England National Primate Research Center (NEPRC) to the SNPRC in the fall of 2014. The new colony will be maintained in buildings physically separate from the existing SNPRC rhesus colony, and is expected to grow to a steady state of approximately 540 individuals over a five year period. This application seeks to augment SNPRC's capacity to house SPF rhesus macaques through renovation of an existing building (Building 109) to provide a total of 10,819 net square feet of social group housing. The project is needed to accommodate the growth of the NEPRC colony between the time of arrival and reaching steady state. The proposed renovation will replace existing cage components, especially chain-link fencing materials, which are worn from use and designed to accommodate cynomolgus macaques. Fourteen existing cages will be subdivided to provide 28 smaller indoor/outdoor cages to efficiently house rhesus harems of up to 10 adults. In conjunction with another project (Building 111) already underway at SNPRC, this proposed project will house the entire NEPRC colony when it reaches steady state. Completion of this renovation will permit SNPRC to support recent and planned increases in faculty at the Texas Biomedical Research Institute as well as the needs of outside investigators.